Ovarian cancer risk seen in DES grand-daughters

NEW YORK (Reuters Health) - Women whose mothers were exposed to diethylstilbestrol (DES) in the womb appear to be at increased risk of developing ovarian cancer, researchers report in the journal Epidemiology.

DES, a synthetic form of estrogen, was introduced in 1941 as a drug that prevented miscarriage. An estimated 6 million women worldwide took the drug before its use during pregnancy was banned in 1971 when it was linked to cancer in the reproductive organs of females exposed to DES before birth.

Subsequently, other problems were seen in sons and daughters of women who took DES, and now it seems that the hazard may have been passed to grand-daughters.

However, Dr. Linda Titus-Ernstoff told Reuters Health, "Because our findings are based on only three cases, they must be considered preliminary."

Titus-Ernstoff, of Dartmouth Medical School, Lebanon, New Hampshire, and colleagues studied data on the children of women who had verified DES exposure or no DES exposure before birth.

The data included mothers' reports of cancers occurring in 8216 children, along with confirmed cancers and benign diagnoses self-reported by a subset of 793 daughters.

Statistically, the findings are not very strong, say the investigators, but "our data are consistent with no overall increase of cancer in the sons or daughters of women exposed in utero to DES."

However, although there was no overall increase in cancer, there were three cases of ovarian cancer in daughters of women exposed prenatally to DES -- a figure higher than would normally be expected.

Titus-Ernsdoff concludes that the findings, "considered together with the results of animal studies, raise the possibility that environmental contaminants may influence the health of future generations."

SOURCE: Epidemiology, March 2008.